DUP councillor Luke Poots is to withdraw as chair of Lisburn and Castlereagh City Council's planning committee whenever his MLA father Edwin makes representations.

Mr Poots made the announcement yesterday after it was revealed that the Northern Ireland Ombudsman was investigating a complaint lodged by the Green Party concerning a potential conflict of interest.

The councillor said that during the ongoing investigation he would withdraw from committee meetings whenever his father, who was once in charge of planning for Northern Ireland as Minister for the Environment, lobbies councillors.

In a statement, he added: "On being appointed to the planning committee of Lisburn Castlereagh City Council, I asked for advice on my role if my father made representations to the committee.

"The council received legal advice from their independent legal advisers, which I have always followed.

"Until the ombudsman completes this investigation into the Green Party's pernicious complaint, to further reinforce public confidence I will not participate in the committee when my father makes a representation."

The Green Party lodged a complaint with the ombudsman claiming there had been a conflict of interest in decisions on which Edwin Poots lobbied the council while Luke sat as chair of the committee.

The Northern Ireland Audit Office advises that a perception of a conflict of interest "can be just as significant as an actual conflict of interest". Both men deny any wrongdoing, insisting that independent legal advice was taken on the matter and followed at all times.

Luke Poots said every time his father had lobbied on a matter, he had declared an interest.

"I have done everything by the book," he said. "I am 100% in the clear. Every time I have been in the chair when my dad speaks, I have declared an interest."

Edwin Poots claimed the Green Party's allegations were "political mischief" and insisted there was no substance to them.

"Rather than allowing the ombudsman to do the work, they have then gone to the media," he said.

"There is not an allegation of substance that has been made.

"This is purely an attempt to do politics by smear and innuendo, with no evidence base for any wrongdoing whatsoever.

"This is not the first time the Greens have done this. Last year they reported me to the Assembly ombudsman on a separate issue, which was immediately thrown out."

Edwin Poots also rejected any possible perception of a conflict of interest.

"From the first meeting Luke sat on, he sought the direction of the council," he said.

"It took independent legal advice, and he has followed the protocol from the outset.

"There has not been a perception, there has been dozens of meetings subsequently and this is a creation of the Green Party and some of their supporters. It is pernicious and it is nasty."

Green Party leader Steven Agnew said they received a complaint that was referred to the ombudsman.

"It is important that our planning system is above board and is seen to be above board," Mr Agnew added.

In a statement, the party said: "The Green Party cannot comment any further on this case because it is a live investigation, but it can confirm that the complaint was made after the issue was raised with Steven Agnew by a Green Party member."